/* SPDX-License-Identifier: GPL-2.0-or-later */ #include <arch/exception.h> #include <types.h> #include <console/console.h> #include <device/mmio.h> #include <ramdetect.h> #include <arch/smp/spinlock.h> #include <vm.h> static enum { ABORT_CHECKER_NOT_TRIGGERED, ABORT_CHECKER_TRIGGERED, } abort_state = ABORT_CHECKER_NOT_TRIGGERED; extern void (*trap_handler)(struct trapframe *tf); static int get_instruction_len(uintptr_t addr) { uint16_t ins = read16p(addr); /* * 16-bit or 32-bit instructions supported */ if ((ins & 0x3) != 3) { return 2; } else if ((ins & 0x1f) != 0x1f) { return 4; } die("Not a 16bit or 32bit instruction 0x%x\n", ins); } static void ramcheck_trap_handler(struct trapframe *tf) { abort_state = ABORT_CHECKER_TRIGGERED; /* * skip read instruction. */ int insn_size = get_instruction_len(tf->epc); write_csr(mepc, read_csr(mepc) + insn_size); } int probe_mb(const uintptr_t dram_start, const uintptr_t size) { uintptr_t addr = dram_start + (size * MiB) - sizeof(uint32_t); void *ptr = (void *)addr; abort_state = ABORT_CHECKER_NOT_TRIGGERED; trap_handler = ramcheck_trap_handler; barrier(); read32(ptr); trap_handler = default_trap_handler; barrier(); printk(BIOS_DEBUG, "%lx is %s DRAM\n", dram_start + size * MiB, abort_state == ABORT_CHECKER_NOT_TRIGGERED ? "" : "not"); return abort_state == ABORT_CHECKER_NOT_TRIGGERED; }